A novel solution to improve saddle-shape warpage in 3D NAND flash memory

摘要

It is difficult to adjust asymmetrically saddle-shape wafer warpage resulted from high-stress material in 3D NAND Flash memory. This paper proposes a novel method that the suitable trenches on the backside of wafer is formed to improve saddle-shape warpage asymmetrically. Effects of different trench pitches, CDs and depths are studied by FEM (finite element method) simulation. This solution provides an instruction for solving warpage in 3D NAND flash memory manufacturing.